1. Field of the Invention
The present invention generally relates to devices for interconnecting data transmission lines, and more particularly to a low profile connector for aligning optical fibers with optoelectronic components along the edge of a circuit board.
2. Description of the Prior Art
The use of optical fibers for high speed communication and data transmission via optical signals has become well established. There are already hundreds of thousands of miles of optical fiber in use today. As with copper wires, it is necessary to provide connections between optical fibers at various locations in the distribution system, whether during the installation of new fibers, or during the repair or replacement of existing fibers. It has, therefore, become imperative to provide optical fiber connectors which may be inexpensively manufactured, as well as easily assembled in the field or on customer premises, to provide connections between existing fibers and electro-optical (optoelectronic) devices. As used herein, the term "connector" refers to a detachable and refastenable device, as opposed to a "splice" which usually connotes a permanent connection.
There are several conventional optical fiber connector designs, including those commonly referred to as ST, SC, FC, D4, SMA, and biconic connectors. Each of these designs are simplex, i.e., they are used to connect a single pair of fibers, although they may be adapted for duplex use. Other connectors have been specifically designed for duplex connections, including those shown in U.S. Pat. Nos. 4,611,887, 4,762,388, 4,779,950, 4,979,792 and 5,016,968. The connector design shown in the latter two patents is referred to as FDDI, for Fiber Distributed Data Interface, and is probably the closest prior art to the present invention. This connector employs ferrule technology and is used, among other things, for data transmission and reception between computer systems, particularly local area networks. Another device known as an ESCON connector is very similar to the FDDI connector but additionally has a retractable shroud to protect the ferrules.
One need that has still not been met by FDDI and other fiber optic connectors is the demand for an efficient mass connection system for a high-density environment, particularly for a data processing system, such as a mainframe computer or a telecommunications switching system. A major problem is that conventional connectors are too large, both in overall bulk and more importantly in the ferrule-to-ferrule spacings. An alternative to ferrule technology is expanded beam technology, but this format is very costly. Most of the prior art designs further require numerous components, adding to cost which becomes very significant in a mass connection system.
There is also a need for an optical connector which physically cooperates with or conforms to a bank or array of connectors which may include side-by-side fiber and copper connections. For example, in some prior art computer systems, the connectors are designed to provide for the quick, mass disconnection of all of the connectors on a given circuit card, allowing removal of the card from the chassis of the computer. It would, therefore, be desirable and advantageous to devise a low-profile connector for providing a high-quality connection to optoelectronic components in a very high density interconnection environment. The connectors should be modular, and compatible with existing systems having copper connectors, and should further be adapted to easily provide fiber-to-fiber connections.